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perf intel-pt: Rename intel-pt.txt and put it in man page format
Make the Intel PT documentation into a man page. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lore.kernel.org/lkml/20200311122034.3697-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Intel Processor Trace
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=====================
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perf-intel-pt(1)
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================
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Overview
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========
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NAME
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----
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perf-intel-pt - Support for Intel Processor Trace within perf tools
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SYNOPSIS
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--------
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[verse]
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'perf record' -e intel_pt//
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DESCRIPTION
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-----------
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Intel Processor Trace (Intel PT) is an extension of Intel Architecture that
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collects information about software execution such as control flow, execution
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@ -43,7 +52,7 @@ vary depending on the use-case and architecture.
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Quickstart
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==========
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----------
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It is important to start small. That is because it is easy to capture vastly
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more data than can possibly be processed.
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@ -156,10 +165,10 @@ for more details.
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perf record
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===========
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-----------
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new event
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---------
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~~~~~~~~~
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The Intel PT kernel driver creates a new PMU for Intel PT. PMU events are
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selected by providing the PMU name followed by the "config" separated by slashes.
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@ -245,7 +254,7 @@ perf_event_attr is displayed if the -vv option is used e.g.
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config terms
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------------
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~~~~~~~~~~~~
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The June 2015 version of Intel 64 and IA-32 Architectures Software Developer
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Manuals, Chapter 36 Intel Processor Trace, defined new Intel PT features.
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@ -435,7 +444,7 @@ pwr_evt Enable power events. The power events provide information about
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AUX area sampling option
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------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~
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To select Intel PT "sampling" the AUX area sampling option can be used:
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@ -485,7 +494,7 @@ but the tool validates that the sample size is not greater than 60KiB.
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new snapshot option
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-------------------
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~~~~~~~~~~~~~~~~~~~
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The difference between full trace and snapshot from the kernel's perspective is
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that in full trace we don't overwrite trace data that the user hasn't collected
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@ -514,7 +523,7 @@ The snapshot size is displayed if the option -vv is used e.g.
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new auxtrace mmap size option
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---------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Intel PT buffer size is specified by an addition to the -m option e.g.
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@ -547,7 +556,7 @@ The mmap size and auxtrace mmap size are displayed if the -vv option is used e.g
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Intel PT modes of operation
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---------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Intel PT can be used in 2 modes:
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full-trace mode
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@ -577,7 +586,7 @@ The 2 modes cannot be used together.
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Buffer handling
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---------------
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~~~~~~~~~~~~~~~
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There may be buffer limitations (i.e. single ToPa entry) which means that actual
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buffer sizes are limited to powers of 2 up to 4MiB (MAX_ORDER). In order to
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@ -601,7 +610,7 @@ data.
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Intel PT and build ids
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----------------------
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~~~~~~~~~~~~~~~~~~~~~~
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By default "perf record" post-processes the event stream to find all build ids
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for executables for all addresses sampled. Deliberately, Intel PT is not
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@ -619,7 +628,7 @@ If the perf.data file contains Intel PT data, that is the same as:
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Snapshot mode and event disabling
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---------------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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In order to make a snapshot, the intel_pt event is disabled using an IOCTL,
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namely PERF_EVENT_IOC_DISABLE. However doing that can also disable the
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@ -642,7 +651,7 @@ To run the test:
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perf record modes (nothing new here)
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------------------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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perf record essentially operates in one of three modes:
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per thread
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@ -668,7 +677,7 @@ mode by using the --per-thread option.
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Privileged vs non-privileged users
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----------------------------------
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Unless /proc/sys/kernel/perf_event_paranoid is set to -1, unprivileged users
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have memory limits imposed upon them. That affects what buffer sizes they can
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@ -697,7 +706,7 @@ be possible to decode Intel PT in per-cpu mode.
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sched_switch tracepoint
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-----------------------
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~~~~~~~~~~~~~~~~~~~~~~~
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The sched_switch tracepoint is used to provide side-band data for Intel PT
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decoding in kernels where the PERF_RECORD_SWITCH metadata event isn't
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@ -783,14 +792,14 @@ cannot be matched against the Intel PT trace.
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perf script
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===========
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-----------
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By default, perf script will decode trace data found in the perf.data file.
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This can be further controlled by new option --itrace.
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New --itrace option
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-------------------
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~~~~~~~~~~~~~~~~~~~
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Having no option is the same as
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@ -913,7 +922,7 @@ at the beginning. This is useful to ignore initialization code.
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skips the first million instructions.
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dump option
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-----------
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~~~~~~~~~~~
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perf script has an option (-D) to "dump" the events i.e. display the binary
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data.
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@ -931,7 +940,7 @@ To disable the display of Intel PT packets, combine the -D option with
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perf report
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===========
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-----------
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By default, perf report will decode trace data found in the perf.data file.
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This can be further controlled by new option --itrace exactly the same as
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@ -939,7 +948,7 @@ perf script, with the exception that the default is --itrace=igxe.
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perf inject
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===========
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-----------
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perf inject also accepts the --itrace option in which case tracing data is
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removed and replaced with the synthesized events. e.g.
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@ -977,7 +986,7 @@ that may change in the future if greater use is made of the data.
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PEBS via Intel PT
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=================
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-----------------
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Some hardware has the feature to redirect PEBS records to the Intel PT trace.
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Recording is selected by using the aux-output config term e.g.
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